Pile fabrics are commercially produced in various conventional ways, such as applying tufting to a backing material, or by cutting between a double woven or double knit construction. It both cases continuous multifilament bulked yarn is often used to provide the upstanding pile fibers. The appearance of the final product is a major concern, and one significant factor governing appearance is the texture of the pile fabrics. Hence, it has been conventional to try to maintain uniform texture of the pile, by avoiding variations in the processing of the yarn from the time it is spun until completion of the pile fabric. However uniformly the yarn and fabric may be made, there will still be occasions when abberations of the machinery for incorporating the yarn into the fabric will result in small flaws, such as slubs or streaking, which will be faintly visible on close inspection of the pile but which do not otherwise affect the usefulness of the fabric. For purposes of economy it is desirable to avoid scrapping fabric with such flaws, and hence there has been a long standing need for a method of preventing such flaws from marring the appearance of the fabric to a commercially significant degree.